Addition of 1, 1 ether-esters to olefins



ADDITION OF 1,1 ETHER-ESTERS T OLEFINS John W. Copenhaver, Short Hills,N. J., assignor to General Aniline & Film Corporation; New York, N. Y.,a corporation of Delaware No Drawing; Application June29, 1951, SerialNo. 234,446

18 Claims. (Cl. 260488) in which R, R and R are inert monovalentaliphatic, aromatic or alicyclic radicals, preferably hydrocarbonradicals, for example alkyl, aryl, aralkyl, cycloalkyl, and morepreferably lower alkyl radicals. The corresponding ether-alcohols andether-enes may be produced from these ether-esters by saponification anddealcoholization.

it will be noted that this reaction involves a splitting of the acyloxyor aroyloxy group from the 1,1 ether-ester and migration of theresulting radicals of the 1,1 etherester to saturate the ethyleniccompound thereby producing a mixed 1,3 ether-ester.

As examples of 1,1 ether-esters which may be employed in practicing thepresent invention may be mentioned the esters of acetic, propionic,butyric, benzoic, hexahydrobenzoic, cyclohexylacetic, phenylacetic acidsand the like with alcohols, such as the ethyl, propyl, butyl, allyl,

ired States Patent 0 cyclohexyl, benzyl and phenylethyl alcohols,substituted in the alpha position by ether groups such as methoxy,ethoxy, butyloxy, cyclohexyloxy, phenoxy'and the like. The lower acyloxyand alkoxy derivatives are preferred, such as alpha methoxy methylacetate, alpha ethoxy ethyl butyrate, alpha butyloxy propyl acetate,alpha propyloxy butyl propionate and the like. It will, of course, beunderstood that 1,1 ether-esters substituted by inert radicals which donot interfere with the production of the desired products in the desiredreaction are to be included within the scope of the invention andclaims.

Those 1,1 ether-esters are in general well known'and may be produced bythe reaction of any of the following components: 1) an organiccarboxylic acid and a vinyl ether, 2) an organic carboxylic acid and anacetal, and 3) an acid anhydride and a hemi-acetal. For example, 1,1ether-esters may be termed esters of hemi-acetals which in turn arederived from the addition of one mol of an alcohol to one mol of analdehyde in accordance with the following reaction:

in which R, 'R and R have the values given above.

2,723,287 Patented Nov. 8, 1955 As examples of hydrocarbons containingan activated ethylenically unsaturated group which may be employed inpracticing the present invention may be mentioned styrenes, isobutylene,diis'obutylene and the like. Thus the term hydrocarbon containing anactivated ethylenically unsaturated group as employed herein and in theappended claims is intended to denote the foregoing compounds and smilarcompounds operative in the present invention in which a carbon atom ofsaid group is joined to two other hydrocarbon radicals in branched chainrelationship, or said group is in conjugated relationship with anotherethylenicaly unsaturated group. Compounds such as ethylene, propylene,cyclohexene, and the like which do not contain a branched chain orconjugated configuration, have been found to be insufiiciently active toundergo the desired addition reaction.

' The catalyst employed in practicing the present invention is anacid-reacting condensing agent. As examples of suitable catalysts theremay be mentioned such acidreacting condensing agents as borontrifluoride and its complexes with ether, boron trichloride, galliumtrichloride, stannic chloride, titanium chloride, p-toluenesulfonicacid, sulfuric acid and the like. The amount of catalyst is not highlycritical and may be varied from mere traces to about 0.1 mol of catalystper mol of acylal. However, for best results, employing a catalyst likeboron trifiuoride, amounts within the range of 0.0025 to 0.01 mol ofcatalyst per mol of acylal are employed.

In general, the catalyst should be added carefully to the 1,1ether-ester with cooling and stirring to avoid any tendency for the 1,1ether-ester to disproporitionate to the ethylidene diacylate and thecorresponding acetal,

viz.

In order to avoid this reaction, it is also necessary to run theaddition reaction under generally mild conditions of from about 0 to 35C.

Generally, anhydrous conditions should be maintained and diluents may beemployed, although there is no particular advantage inherent in the useof a diluent. After the reaction has been completed, the catalyst may beneutralized with any base or alkali, although the use of strong alkaliesmust be controlled to avoid saponification 'ofthe ester. Preferablyanhydrous solvent-soluble bases of the type of triethanolamine,diethanolamine, ethanolamine, sodium methylate, ammonia, pyridine andthe like should be employed. After neutralization the reaction productmay be isolated generally by distillation. The use of pressure may befound useful in some cases, as for example, in order to keep a gaseousolefin such as isobutylene in the reaction. I

The following examples present specific embodiments of the invention,although it is to be understood that the invention is not to be limitedthereby.

Example 1.-Preparati0n of the acetate of phnyl-Z-methoxy-propyl carbinolthe catalyst neutralized. Distillationgave the acetate ofphenyl-Z-methoxy-propyl carbinol, boiling at 122 v C./ 9 min, N 1.4852.

Analysis.-Calc. for C13H1a03i C, 70.23; H, 8.16. Found: C, 69.93; H,8.35.

The reaction may be formulated as follows:

Acetate of pheny1-2-methoxy-propyl carbinol Example 2.Preparatin ofphenyl-Z-methoxy-propyl Carbinol 168 g. of diisobutylene were addeddropwise over 1.25 hours keeping the temperature at 3-5 C. The reactionThis example illustrates Sapollificafioh 0f the mixture was stirred at05 for 5 hours, then let stand ester of the previous example to producth correspondovernight in an ice box at about 5-10 C. The solution ing2,4-ether-alcohol. was then treated with 1200 ml. of 10 percent sodiumhyof the acetate 0f p yp py ealhihol 20 droxide and then refluxed for 2hours. The organic layer were refluxed 6 hours With a lu i n 0f 5 giumY- was separated, washed with water and distilled to yield droxide in 50Water- The y layer Was Separated. 97 g. of2,2,4-trirnethyl-6-methoxyheptene-3, B. P. 70 taken up in ether, washedwith water, dried and distilled C 15 mm., N 1.4283 and 22 g. of2,2,4-trimethyl-6- to give P Y Y p py nol. B- P. 93 C./ 1methoxyheptanol-4, B. P. 105 c./s mm., N 1.4421. mm, N 1.5050.Analysis.Calc. for C11H24O2: C, 70.16; H, 12.85.

This product is a secondary alcohol as shown by the Found: C, 70.84; H,11.76. fact that it gave a rapid test with ZnClaHCl solution. The reation may be formulated as follows:

E 0on3 CH3 H CH3 H3CC/ +HaC CH:

OC-CHa H: H l

a-Methoxy ethyl acetate dilsobutylene Example 3.Preparation 0] theacetate 0) 2-methyl-4- methoxypentanol-Z 540 g. (5 mol) ofa-methoxyethyl acetate (acylal) were charged to a 1-liter, 3-neckedflask fitted with a sealed stirrer, thermometer, gas inlet tube andconnected to a dry ice-methanol cooled trap. After cooling to about 5C., 5 ml. of'boron fluoride etherate were added slowly H 0 CH3 CH3 CH31'1 HsC- CH3-$=CH2 CH3( '-OH2 C CH3 Off-CH; (ll-CH; OCHa a-Methoxy ethylIsobutylene Acetate of 2-methyl-4- acetate methoxy pentanol-2 Example4.-Preparati0n 0) 2-methyl-4-meth0xypentanol-Z This example illustratesthe saponification of the 2,4-

ether-ester of the previous example to the corresponding 2,4ether-alcohol.

174 g. (1 mole) of the acetate of 2rnethyl-4-methoxypentanol-2 wereadded to a solution of 40 g. (1 mole) 'of sodium hydroxide in 200 ml. of50% aqueous ethanol.

The reaction mixture was refluxed 2 hours, cooled, n

H CH: H OH; H

2,2,4-trimethyl-6-methoxy-heptene-3 As will be apparent from thedescription of the invention set forth hereinbefore, the term 1,3ether-ester is employed both in the disclosure and in the appendedclaims to mean compounds in which ether and ester groups are in 1,3 or3,1 position relative to each other only in a carbon chain. They thusinclude 2,4-ether-esters or estercthers, 3,5-ether-esters orester-ethers, etc., all of which may be regarded as substituted1,3-ether-esters. Stated otherwise, they are compounds in which theether and ester groups are attached to two consecutive alternate carbonatoms in a carbon chain.

The products of the present invention are useful as chemicalintermediates, for example, for saponification to ether-alcohols and thelike, as solvents, plasticizers, etc.

My invention has been described with respect to certain preferredembodiments thereof but various modifications and variations Within thespirit and scope of the invention will become apparent to those skilledin the art. It is accordingly understood that such modifications andvariations are to be considered as within the purview of thisapplication and the scope of the appended claims.

I claim:

1. A process for producing mixed 1,3 ether-esters which comprisesreacting, at a temperature of about 0 to 35 C., a compound of theformula:

H OR 1116 wherein R, R andR are selected from the group consisting ofalkyl, aralkyl, aryl and cycloalkyl radicals containing no more thanabout 8 carbon atoms, with an ethylenically unsaturated compoundselected from the group consisting of styrene, isobutylene anddiisobutylene in the presence of an acid-reacting condensing agent.

2. A process as defined in claim 1 wherein the acid reacting condensingagent is boron fluoride.

3. A process as defined in claim 1 wherein the ethylenically unsaturatedcompound is styrene.

4. A process as defined in claim 1 wherein the ethylenically unsaturatedcompound is isobutylene.

5. A process as defined in claim 1 wherein the ethylenically unsaturatedcompound is diisobutylene.

6. A process which comprises reacting, at a temperature of about 0 to 35C., a compound of the formula:

H 0B. Rub

oo-m

wherein R, R and R are selected from the group consisting of alkyl,aralkyl, aryl and cycloalkyl radicals containing no more than about 8carbon atoms, with an ethylenically unsaturated compound selected fromthe group consisting of styrene, isobutylene and diisobutylene in thepresence of an acid-reacting condensing agent to produce a mixed 1,3ether-ester, and saponifying said ether-ester to the corresponding 1,3ether-alcohol.

7. A process which comprises reacting, at a temperature of about 0 to 35C., a compound of the formula:

wherein R, R and R are selected from the group consisting of alkyl,aralkyl, aryl and cycloalkyl radicals containing no more than about 8carbon atoms, with an ethylenically unsautrated compound selected fromthe group consisting of styrene, isobutylene and diisobutylene in thepresence of an acid-reacting condensing agent to produce a mixed 1,3ether-ester, and saponifying and dealcoholizing the said ether-ester tothe corresponding l-ether-3-ene.

8. A process for producing the acetate of phenyl-2- methoxy-propylcarbinol by reacting, at a temperature of 6 about 0 to 35 C.,alpha-methoxy ethyl acetate with styrene in the presence of boronfluoride.

9. A process comprising reacting, at a temperature of about 0 to 35 C.,alpha-methoxy ethyl acetate with styrene in the presence of boronfluoride and saponifying the reaction product thereof to producephenyl-Z-methoxy-propyl carbinol.

10. A process for producing the acetate of 2-inethyl-4-methoxy-pentanol-Z by reacting, at a temperature of about 0 to 35 C.,alpha-methoxy ethyl acetate with isobutylene in the presence of boronfluoride.

11. The process for producing the acetate of2,2,4-trimethyl-6-methoxyheptanol-4 by reacting, at a temperature ofabout 0 to 35 C., alpha-methoxy ethyl acetate with diisobutylene in thepresence of boron fluoride.

12. The process comprising reacting, at a temperature of about 0 to 35C., alpha-methoxy ethyl acetate with diisobutylene in the presence ofboron fluoride and saponifying and dealcoholizing the reaction productthereof to produce a mixture of 2,2,4-trimethyl6-methoxy-heptanol- 4 and2,2,4-trimethyl-6-methoxy-heptene-3.

13. The acetate of phenyl-Z-methoxy-propyl carbinol.

14. The acetate of 2-methyl-4-methoxy-pentanol-Z.

15. The acetate of 2,2,4-trimethy1-6-methoxyheptanol-4.

16. PhenyI-Z-methoxy-propyl carbinol.

17. 2,2,4-trimethyl-6-methoxy-heptene-3.

18. A compound having the formula in which R is selected from the groupconsisting of H and R, R and R are selected from the group consisting ofalkyl, aralkyl, aryl and cycloalkyl radicals containing no more thanabout 8 carbon atoms and the portion in brackets is the residue of anethylenically unsaturated compound selected from the group consisting ofstyrene, isobutylene and diisobutylene.

References Cited in the file of this patent UNITED STATES PATENTS2,446,171 Croxall et a1 Aug. 3, 1948

1. A PROCESS FOR PRODUCING MIXED 1,3 ETHER-ESTERS WHICH COMPRISESREACTING, AT A TEMPERATURE OF ABOUT 0 TO 35* C., A COMPOUND OF THEFORMULA: